reached maximum number of iterations on binary search

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1

i write the input files. And openmc was down at 186th batches. And when i input the energy grid “union” in settings.xml, it stopped at creating energy grid. Who have met this before? how to solve it?
I’m using ace data produced by ENDFB70

Here are my input files:

<?xml version="1.0"?> 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 3 1 1 3 1 1 3 1 1 1 1 1 1 1 1 3 1 1 1 1 1 1 1 1 1 3 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 3 1 1 3 1 1 3 1 1 3 1 1 3 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 3 1 1 3 1 1 3 1 1 3 1 1 3 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 3 1 1 3 1 1 3 1 1 3 1 1 3 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 3 1 1 1 1 1 1 1 1 1 3 1 1 1 1 1 1 1 1 3 1 1 3 1 1 3 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 <?xml version="1.0"?> cross_sections.xml 600 50 10000 nuclide 0.63 0.63 0
2

Setting <energy_grid>union</energy_grid> tells OpenMC you want to create pointers on a unionized energy grid to speed up searches on energy for each nuclide’s energy grid. The theory and methodology guide describes this in detail:
http://mit-crpg.github.io/openmc/methods/cross_sections.html#energy-grid-methods

The problem is most likely that your computer does not have enough memory to store all the union energy grid pointers. How many nuclides do you have in your problem?

Best regards,
Paul

3

Hi Paul,
thanks for your reply.
i’m not sure what you mean when you say nuclide. in one batch, i set 10000 particles. For materials, it contains six isotopes. the material file is as follows:just for this file, Openmc was down at either 236th batch or 187th. it seems wired.
Best wishes,
SHEN Qicang

<?xml version="1.0"?>

在 2014年5月22日星期四UTC+8上午5时51分37秒，Paul Romano写道：

4

Hi Shen,

What cross sections are you using? e.g. ENDF/B-VII.1

Paul